• 제목/요약/키워드: Processing aid

검색결과 275건 처리시간 0.019초

웨이브렛 변환과 자동적인 임계치 설정에 의한 미세 석회화 검출 (Microcalcification Extraction by Wavelet Transform and Automatic Thresholding)

  • 원철호;서용수;조진호
    • 한국멀티미디어학회논문지
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    • 제8권4호
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    • pp.482-491
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    • 2005
  • 본 논문에서는 디지털 X선 유방 촬영 시스템에서 획득된 영상으로부터 웨이브릿 변환과 자동적인 임계치 설정기법을 이용하여 미세 석회화 영역을 추출하였다. 디지털 X선 영상 장비는 임상 진단 분야에서는 필수적인 진단 장비이며, 흉부 촬영, 골절상 및 치아 교정 등의 다양한 분야에 사용되고 있다. 특히 디지털 X선 유방 촬영술은 유방암 진단의 가장 좋은 방법으로 알려져 있으며 최근 국내에서 디지털 X선 기기를 개발하기 위한 많은 연구들이 진행되고 있다. 본 논문에서는 디지털 X선 유방 촬영 영상으로부터 초기 단계의 유방암 진단을 위해 필수적인 미세 석회화를 검출하는 알고리즘을 제안하여 이를 효과적으로 검출하였으며 진단 방사선학적 진단에 도움을 줄 수 있음을 보였다.

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Development Brief of A Body Area Network for Ubiquitous Healthcare : An Introduction to Ubiquitous Biomedical Systems Development Center

  • Hong Joo-Hyun;Kim Nam-Jin;Cha Eun-Jong;Lee Tae-Soo
    • 대한의용생체공학회:의공학회지
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    • 제26권5호
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    • pp.331-335
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    • 2005
  • The fusion technology of small sensor and wireless communication was followed by various application examples of the embedded system, where the social infrastructural facilities and ecological environment were wirelessly monitored. In addition, this technology represents the primary application area being extended into the healthcare field. In this study, a body area network for ubiquitous healthcare is presented. More specifically this represents a wireless biomedical signal acquisition device characterized by small size, low power consumption, pre-processing and archiving capability. Using this device, a new method for monitoring vital signs and activity is created. A PDA-based wireless sensor network enables patients to be monitored during their daily living, without any constraints. Therefore, the proposed method can be used to develop Activities of Daily Living (ADL) monitoring devices for the elderly or movement impaired people. A medical center would be able to remotely monitor the current state of elderly people and support first-aid in emergency cases. In addition, this method will reduce medical costs in society, where the average life expectancy is increasing.

반응소결법 및 통전가압소결법에 의한 $Ti_5Si_3$계 금속간화합물의 합성 및 치밀화 (Synthesis and Densification of $Ti_5Si_3$-base Intermetallic Compounds by Reactive Sintering and Electro-Pressure Sintering)

  • 유호준
    • 한국분말재료학회지
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    • 제4권4호
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    • pp.283-290
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    • 1997
  • $Ti_5Si_3$ intermetallics containing 0-6 wt% of Cu were made by reactive sintering (RS) under vacuum using elemental powder mixtures (Process 1), electro-pressure sintering (EPS) using RS'ed materials (Process2), and EPS using elemental powder mixtures (Process 3). Relatively low dense titanium silicides were gained by process 1, in which porosity decreased with increasing Cu content. For example, porosity changed from 42 to 19.4% with the increase in Cu content from 0 to 6 wt%, indicating that Cu is a useful sintering aid. The titanium silicides fabricated by Process 2 had a higher density than those by Process 1 at given composition, and porosity decreased with increasing Cu content. For example, porosity decreased from 38 to 6.8% with the change in Cu content from 0 to 6 wt%. A high dense titanium silicides were obtained by Process 3. In this Process, porosity decreased a little by Cu addition, and was almost insensitive to Cu content. Namely, about 9 or 7% of porosity was shown in 0 or 1-6 wt% Cu containing silicides, respectively. The hardeness increased by Cu addition, and was not changed markedly with Cu content for the silicides fabricated by Process 3. This tendency was considered to be resulted from porosity, hardening of grain interior by Cu addition, and softening of grain boundary by Cu-base segregates. All these results suggested that EPS using elemental powder mixtures (Process 3) is an effective processing method to achieve satisfactorily dense titanium silicides.

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Assessment of Breast Cancer Risk in an Iranian Female Population Using Bayesian Networks with Varying Node Number

  • Rezaianzadeh, Abbas;Sepandi, Mojtaba;Rahimikazerooni, Salar
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권11호
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    • pp.4913-4916
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    • 2016
  • Objective: As a source of information, medical data can feature hidden relationships. However, the high volume of datasets and complexity of decision-making in medicine introduce difficulties for analysis and interpretation and processing steps may be needed before the data can be used by clinicians in their work. This study focused on the use of Bayesian models with different numbers of nodes to aid clinicians in breast cancer risk estimation. Methods: Bayesian networks (BNs) with a retrospectively collected dataset including mammographic details, risk factor exposure, and clinical findings was assessed for prediction of the probability of breast cancer in individual patients. Area under the receiver-operating characteristic curve (AUC), accuracy, sensitivity, specificity, and positive and negative predictive values were used to evaluate discriminative performance. Result: A network incorporating selected features performed better (AUC = 0.94) than that incorporating all the features (AUC = 0.93). The results revealed no significant difference among 3 models regarding performance indices at the 5% significance level. Conclusion: BNs could effectively discriminate malignant from benign abnormalities and accurately predict the risk of breast cancer in individuals. Moreover, the overall performance of the 9-node BN was better, and due to the lower number of nodes it might be more readily be applied in clinical settings.

Food Composition Database in Korea

  • Chun, Hye-Kyung;Park, Hong-Ju;Lee, Sung-Hyeon
    • Nutritional Sciences
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    • 제7권1호
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    • pp.47-52
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    • 2004
  • The food composition database is used to evaluate the nutritional value of foods in Korea. It is used as a source for basic data in many fields, not only for the establishment of the National Food Supply Plan but also for nutritional research, to aid in the drafting of the National Food Policy, and in clinical and epidemiological research. The database is also used by institutional and commercial food services and by the food processing industry among others. In 1970, the Rural Development Administration(RDA) published the "Korean Food Composition Table" for the first time and it has since become the established authority on food composition for the entire nation. The latest published food composition table (the 6th edition, published by the National Rural Living Science Institute, KDA) covers 2,337 kinds of foods and consists of two volumes. The National Rural Living Science Institute, the Korea Food and Drug Administration, and the National Fisheries Research and Development Institute have continuously improved production of food composition data in Korea. As consumers have grown more interested in the quality and safety of foods and raw agricultural products, we can expect even further development of food composition data through improvements in quality and increases in quantity. We need to develop more comprehensive food composition data by diversifying the kinds of foods that are included, unifying analytical methods, and increasing the number of nutrients covered. Moreover, food composition data must be modified in other ways to make for a better food composition database for the convenience of users. of users.

원양산 오징어(Illex argentinus) 내장으로부터 Endoprotease의 분획 (Fractionation of Endoprotease from Viscera of the Argentina Shortfin Squid Illex argentinus)

  • 김혜숙;김진수;허민수
    • 한국수산과학회지
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    • 제41권3호
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    • pp.176-181
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    • 2008
  • To evaluate the effective use of endoprotease from squid viscera as a food processing aid, various methods of fractionating endoprotease from viscera of the Argentina shortfin squid (Illex argentinus) were evaluated. The endoprotease-positive fractions of each fractionation were fraction II (30-40%, w/w) with cold acetone, fraction IV (50-60% saturation) with ammonium sulfate, fraction UF with anion exchange chromatography, and fraction II (15-24 kDa) with gel filtration. The specific activities (approximately 25 U/mg) of the fractions using ammonium sulfate and gel filtration were higher than the others. Total azocaseinolytic activity and recovery of the positive fraction using gel filtration were 806.95U and 37.82%, respectively, and were the highest among the positive fractions. Based on the results, gel filtration was the most efficient method for fractionating endoprotease from the viscera of Illex argentinus.

High-Frequency Flyback Transformer Linked PWM Power Conditioner with An Active Switched Capacitor Snubber

  • Mun, Sang-Pil;Kim, Soo-Wook;Joo, Seok-Min;Park, Young-Jun
    • 조명전기설비학회논문지
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    • 제22권7호
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    • pp.7-15
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    • 2008
  • A single active capacitor snubber-assisted soft-switching sinewave pulse modulation utility-interactive power conditioner with a three-winding flyback high frequency transformer link and a bidirectional active power switch in its secondary side has been proposed. With the aid of the switched-capacitor quasi-resonant snubber cell, the high frequency switching devices in the primary side of the proposed DC-to-AC sinewave power inverter can be turned-off with ZVS commutation. In addition to this, the proposed power conditioner in the DCM can effectively take the advantages of ZCS turn-on commutation. Its output port is connected directly to the utility AC power source grid. At the end, the prototype of the proposed HF-UPC is built and tested in experiment. Its power conversion conditioning and processing circuit with a high frequency flyback transformer link is verified and the output sinewave current is qualified in accordance with the power quality guidelines of the utility AC interactive power systems.

Evolutionary Optimized Fuzzy Set-based Polynomial Neural Networks Based on Classified Information Granules

  • Oh, Sung-Kwun;Roh, Seok-Beom;Ahn, Tae-Chon
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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    • pp.2888-2890
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    • 2005
  • In this paper, we introduce a new structure of fuzzy-neural networks Fuzzy Set-based Polynomial Neural Networks (FSPNN). The two underlying design mechanisms of such networks involve genetic optimization and information granulation. The resulting constructs are Fuzzy Polynomial Neural Networks (FPNN) with fuzzy set-based polynomial neurons (FSPNs) regarded as their generic processing elements. First, we introduce a comprehensive design methodology (viz. a genetic optimization using Genetic Algorithms) to determine the optimal structure of the FSPNNs. This methodology hinges on the extended Group Method of Data Handling (GMDH) and fuzzy set-based rules. It concerns FSPNN-related parameters such as the number of input variables, the order of the polynomial, the number of membership functions, and a collection of a specific subset of input variables realized through the mechanism of genetic optimization. Second, the fuzzy rules used in the networks exploit the notion of information granules defined over systems variables and formed through the process of information granulation. This granulation is realized with the aid of the hard C- Means clustering (HCM). The performance of the network is quantified through experimentation in which we use a number of modeling benchmarks already experimented with in the realm of fuzzy or neurofuzzy modeling.

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Neo Fuzzy Set-based Polynomial Neural Networks involving Information Granules and Genetic Optimization

  • Roh, Seok-Beom;Oh, Sung-Kwun;Ahn, Tae-Chon
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
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    • pp.3-5
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    • 2005
  • In this paper. we introduce a new structure of fuzzy-neural networks Fuzzy Set-based Polynomial Neural Networks (FSPNN). The two underlying design mechanisms of such networks involve genetic optimization and information granulation. The resulting constructs are Fuzzy Polynomial Neural Networks (FPNN) with fuzzy set-based polynomial neurons (FSPNs) regarded as their generic processing elements. First, we introduce a comprehensive design methodology (viz. a genetic optimization using Genetic Algorithms) to determine the optimal structure of the FSPNNs. This methodology hinges on the extended Group Method of Data Handling (GMDH) and fuzzy set-based rules. It concerns FSPNN-related parameters such as the number of input variables, the order of the polynomial, the number of membership functions, and a collection of a specific subset of input variables realized through the mechanism of genetic optimization. Second, the fuzzy rules used in the networks exploit the notion of information granules defined over systems variables and formed through the process of information granulation. This granulation is realized with the aid of the hard C-Means clustering (HCM). The performance of the network is quantified through experimentation in which we use a number of modeling benchmarks already experimented with in the realm of fuzzy or neurofuzzy modeling.

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Application of an integro-differential equation to the analysis of geotechnical problems

  • Poorooshasb, H.B.;Alamgir, M.;Miura, N.
    • Structural Engineering and Mechanics
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    • 제4권3호
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    • pp.227-242
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    • 1996
  • An important class of problems in the field of geotechnical engineering may be analyzed with the aid of a simple integro-differential equation. Behavior of "rigid" piles(say concrete piles), "deformable" piles(say gravel piles), pile groups, pile-raft foundations, heavily reinforced earth, flow within circular silos and down drag on cylindrical structures (for example the crusher unit of a mineral processing complex) are the type of situations that can be handled by this type of equation. The equation under consideration has the form; $$\frac{{\partial}w(r,\;z)}{{\partial}z}+f(z){\int}^z_0g({\xi})(\frac{{\partial}^2w(r,\;{\xi})}{{\partial}r^2}+\frac{1}{r}\frac{{\partial}w(r,\;{\xi})}{{\partial}r})d{\xi}+h(r,\;z)=0$$ where w(r, z) is the vertical displacement of a soil particle expressed as a function of the polar cylindrical space coordinates (r, z) and the symbols f, g and h represent soil properties and the loading conditions. The merit of the analysis is its simplicity (both in concept and in application) and the ease with which it can be expressed in a computer code. In the present paper the analysis is applied to investigate the behavior of a single rigid pile to bedrock. The emphasis, however, is placed on developing the equation, the numerical techique used in its evaluation and validation of the technique, hereafter called the ID technique, against a formal program, CRISP, which uses the FEM.